A dam has burst its banks in Kenya’s Rift Valley, killing at least 47 people and forcing hundreds from their homes, officials have said.

Water burst through the banks of the Patel dam in Solai, 190km north-west of the capital, Nairobi, at about 9pm on Wednesday. The ensuing deluge swept away hundreds of homes, including those on the expansive Nyakinyua farm, which borders the reservoir.

“Many people are missing. It is a disaster,” said Joseph Kioko, chief of police in the town of Rongai.

Almost an entire village was engulfed by silt and water, said Gideon Kibunja, the Nakuru county police chief in charge of criminal investigations.

More than 40 people were rescued from the mud and taken to hospital in rescue operations conducted by the Kenya Red Cross and Nakuru County disaster management teams. The Red Cross said at least 35 people had been discharged. About 500 households have been displaced.

Many more people are feared to be trapped under debris and mud. Officials said dam water and mud spewed out of the reservoir and submerged homes over a radius of nearly 2km (1.2 miles).

Kenya’s interior cabinet secretary, Fred Matiangi, who arrived at the site to talk with those affected and assess the situation, told reporters the government had launched investigations to determine the stability of six other dams in the area.

It has been suggested that the walls of the dam may have collapsed due to the huge volume of water accumulated as a result of heavy rainfall since March.

Flood water swept through Solai trading centre, destroying almost every structure. Electricity poles fell, causing power outages in at least eight shopping centres in region.

Speaking at Nakuru hospital, Pius Njoroge told the Guardian he was talking to his wife when he heard a loud bang. Suddenly, the whole place was submerged in water. “It happened very fast. There was nowhere to run,” he said.

Roselyn, 22, was watching television with her husband Gordon Odhiambo, 32, when disaster struck. “We were just watching when we heard a big bang from hills behind our house,” the mother-of-three said.

The floods swept through their home and by dawn only the roof was left hanging. Everything inside was gone. “We lost everything but we’re lucky to be alive. It was a narrow escape for us,” said Odhiambo.

A child walks near houses destroyed by flooding after the Patel dam burst. Photograph: Thomas Mukoya/Reuters

At Nyakinywa village, Mariana Wangechi, 25, she her mother, Eunice, 55, was killed in the disaster. Her body was found 2km away on Thursday.

“She [Eunice] was in the kitchen preparing supper and we were in the living room when it happened,” she said.

“I asked her if she heard it and before she answered the whole place had been enveloped by darkness and loud screams,” she said. “I picked up my baby and rushed upwards and that’s how I survived.”

Veronica Wanjiku Ngigi, 67, told Reuters that said she was at home brewing tea yesterday evening when her son’s wife rushed in to say the dam had burst and they needed to get to higher ground immediately.

“It was a sea of water,” she said. “My neighbour was killed when the water smashed through the wall of his house. He was blind so he could not run. They found his body in the morning. My other neighbours also died. All our houses have been ruined.”

According to BBC reports, local leaders want to know whether the farmer who owns the dam was licensed to erect it. There are concerns that two other dams he owns in the area, which are also said to be full, could likewise burst their banks.

Amid mounting scrutiny of the local authorities, Lee Maiyani Kinyanjui, governor of Nakuru County, tweeted: “We assure residents that we are doing our best to evacuate affected families to safety and assist victims [to] get medical attention. We urge residents to be vigilant due to flooding caused by heavy rains experienced in the county and other parts of the country.”

Kenya is already reeling from the effect of the heavy rains and flash flooding that have hit east Africa following months of severe drought.

Before the dam burst, flooding had claimed the lives of more than 130 people since March, the Kenyan government said on Wednesday.

At least 225,436 people have been displaced from their homes, according to a government statement. Military helicopters and personnel have for the past week been deployed to rescue people marooned by the flooding.

The floods hit as the country was recovering from a severe drought that had affected 32 of Kenya’s 47 counties.

Dr Abbas Gullet, the secretary general of Kenya Red Cross, said many of those affected by the floods were suffering from the drought before. “It is a double tragedy and these communities have been rendered more vulnerable because of the cyclical disasters,” he said. “Their coping mechanisms have been totally depleted.”